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Enhancing the durability of catalysts is of critical significance to industrialize green hydrogen production. Herein, a novel active site in situ refreshing strategy is proposed and demonstrated to fabricate highly active and ultra‐durable hydrogen evolution reaction (HER) electro‐catalytic material by HER activation. Briefly, a composite catalytic material is synthesized, which features Ni(PO3)2 active sites being embedded inside the amorphous Mo compound matrix (named NiMoO‐P). The Mo compound matrix undergoes gradual dissolution during HER followed by a dynamic equilibrium between the dissolution and deposition of the amorphous matrix. This process promotes the continuous exposure of insoluble Ni(PO3)2 and Ni2P partially converted from Ni (PO3) 2 in situ on the surface during HER activation. Thus, activated catalyst exhibits excellent HER performance featuring an extremely high current density of 1500 mA cm−2 at a rather low overpotential of 340 mV, and more attractively, an ultra‐long durability for hydrogen evolution for at least 1000 h at an industrial‐applicable current density of 900 mA cm−2. The mechanisms for the especially high HER performance are attributed to the exposure and continuous refreshing of Ni(PO3)2 and the in situ formed Ni2P during the HER process based on the DFT calculations and quasi‐in situ Raman spectroscopic monitoring. [ABSTRACT FROM AUTHOR]

Electrocatalytic glycerol oxidation reaction (GOR) is an effective way to convert biomass byproduct to high value‐added chemicals, which; however, suffers from the low oxidation activity and conversion ratio of the presently available catalysts. Herein, the NiCo2O4/NF bimetallic oxide nanoarray is controllably fabricated by Ni substituting for octahedral Co3+ in Co3O4, which exhibits excellent GOR catalytic activity at elevated current densities (E300 = 1.42 V, E600 = 1.62 V) and overall Faradaic efficiency of 97.5% at 1.42 V (FEformic acid = 89.9% and FEglycolic acid = 7.62%). The high performance is attributed to the structure evolution including the rapid generation of NiIII‐OOH and CoIII‐OOH active species, the optimized intermediates adsorption, and the accelerated electron transfer owing to the Ni introduction, which are evidenced by the operando spectroscopy measurements and density functional theory calculations, respectively. The GOR/hydrogen evolution coupled two‐electrode electrolytic cell voltage is ≈299 mV lower than that of the water splitting at 50 mA cm−2. More importantly, compared to conventional water splitting, this electrolyzer is stable for over 200 h at 1.75 V, reducing energy consumption by 16.9% and obtaining high value‐added products at the anode concurrently. [ABSTRACT FROM AUTHOR]